I'm working on the door panels for my '63. Took them completely apart. Spent 3 hours cutting staples to fit on them perfectly (about 210). The internet says the cardboard part is cardboard but it's not your average cardboard. The back looks like that fake wood cardboard stuff that's completely useless and the front looks like a pie cabinet. One watercooled site said to repair it with plaster strips. I want to know if I can get some at home depot and what it would be called. Uncle jon, I know you've worked on these before. Did you replace the cardboard or have any knowledge about that?